1. Field of the Invention
The present invention relates to a technology for processing and handling stereoscopic images. More specifically, this invention relates to a method and apparatus for synthesizing two-dimensional images and stereoscopic images, a method for ordering an optical filter for use with stereovision, a method, apparatus and system for providing image contents used for stereovision, and a method and apparatus for authenticating users via a network.
2. Description of the Related Art
In the past several years, the population of Internet users has increased explosively, thus setting a new stage in the use of the Internet called the broadband age. The broadband communication with markedly increased communication bandwidths is expected to promote the distribution of heavy image data, which tended to be avoided in the past. With the arrival of the broadband age, such concepts as “multimedia” or “video on demand” can now be experienced by general users for the first time with a sense of reality.
As the distribution of images, especially moving images, expands, it is natural that the users seek greater richness in contents and better image quality. This is mainly due to such efforts and achievements as the digitization of existing image software, the development of authoring tools therefor and the pursuit of image coding technologies featuring higher efficiency and reduced losses.
Under these circumstances, it seems that the industry will focus much attention in the near future on pseudo-three-dimensional images (hereinafter simply referred to also as “three-dimensional images”, “stereoscopic images” or “stereo images”) as a form of digital image contents, which are believed to create a growing market. There are now technological foundations for stereoscopic images that satisfy the wishes of the users for more realistic images and allow them to not simply appreciate them but participate in the creation thereof. This is a new mode of interaction between images and users that has hitherto been unthinkable. Moreover, stereo images will be useful for the realistic presentation of products in EC (electronic commerce) which is believed to become a standard commercial practice in the twenty first century.
There is a technology using parallax images as a technology for showing an object stereoscopically using a two-dimensional display device. FIG. 1 shows a method of stereoscopic vision using parallax images. First, to produce a parallax, there are provided an image to be cast to the right eye (hereinafter referred to simply as “right-eye image 12”) and an image to be cast to the left eye (hereinafter referred to simply as “left-eye image 14”). A basic image 10 is generated by arranging these parallax images alternately at fixed intervals, namely, by thinning them out at every other pixel for instance. This basic image 10 is displayed on a two-dimensional display device.
A stereoscopic vision cannot be obtained by seeing the basic image 10 directly. It is only possible when an optical filter 20 is placed in an intervening space so as to direct the respective parallax images to enter the right eye and the left eye, respectively. For example, the optical filter 20 is an image separation means, such as a parallax barrier or a lenticular lens; in FIG. 1 a parallax barrier is taken as an example. This optical filter 20 is a glass plate on which there are formed stripe patterns that function as slits 16, so that the right-eye image 12 is led to the right eye and the left-eye image 14 is led to the left eye. The pitch of the slits 16 is not fixed and is determined geometrically. At the edges of a screen in particular, the slits will come widely displaced from the front of the pixels. In FIG. 1, the slits 16 are represented schematically, but in reality a very delicate pitch design is carried out based on a relationship of images to the head position of the user.
For a new Internet or network business of distributing stereo images using these technologies, it can be said that there is still neither infrastructure nor models for promoting it. In particular, it is with delicate differences that each user visually captures stereo images, but technology to deal with such an aspect has not been cultivated at least at an actual service level. Moreover, broadening the use of the optical filter 20 is a key to the success of stereo image distribution business.